Science
lab files
Step-by-step lab files, printable data sheets with answer keys, and browser tools for upper elementary, middle and high school science.
// Core skills
Every lab on this site trains the same four skills, in the same order you use them at the bench.
Hypothesize
Write an if, then, because prediction you can test.
Control
Change one variable. Keep every other condition the same.
Measure
Read the meniscus, the balance and the ruler to the right precision.
Explain
Turn the data table and graph into a conclusion.
// Independent vs dependent
Independent
What you change- Chosen before the test
- Plotted on the x-axis
- One per experiment
Dependent
What you measure- Recorded in every trial
- Plotted on the y-axis
- Always has a unit
// Start here
New to lab write-ups? Start with the scientific method, then learn the variables every fair test needs.
// Lab files 6 of 61
Osmosis egg lab
Try an egg osmosis experiment: soak a shell-less egg in water and corn syrup, measure mass change, and explain the direction water moves in this lab.
Gummy bear osmosis
Run a gummy bear osmosis experiment with water, salt water and vinegar; compare mass and size while accounting for gelatin’s limits as a cell model.
Elephant toothpaste
Compare yeast amounts in elephant-toothpaste trials, keep peroxide and other conditions matched, and measure foam rise time and height in class.
Pendulum period
Change pendulum string length, time ten swings, compare periods, and graph period squared against length to investigate the timing pattern in this experiment.
Drops on a penny
Count how many drops of water a penny holds before the dome collapses, then test what soap does to that number.
Strawberry DNA
Run three matched extractions each for 50 g strawberry and banana portions, then compare visible precipitate ratings and variation without assuming either fruit wins.
// Tools
Practice the skill on screen before you need it in the lab.